Vertica shared nothing, no master host.
When you are connected to cluster you are connected to some particular node - this node calls "Executor Node".
"Executor node" distributes each query/task over all nodes and each node do it "self sub-job". When all is done, "Executor Node" collects results from all nodes and returns to user. Very similar to MapReduce strategy.

if i want to install vertica instances in 3 nodes individually , what system functions to be executed or configuration is required to be done to make cluster configuration.
Or what initial settings to be done ??